The objective replacement device according to the present invention is especially useful when used with single plane or selective plane illumination microscopy (SPIM). While confocal laser scanning microscopy is used to scan the specimen point-by-point in a plurality of planes at different depths from which three-dimensional image data of the specimen are subsequently obtained, SPIM technology is based on wide-field microscopy and allows the three-dimensional imaging of the specimen based on optical slices through different planes of the specimen.
The advantages of SPIM technology are, inter alia, the higher speed at which the images are captured, reduced bleaching especially of biological specimens, and a greater depth of penetration of the focus into the specimen.
In SPIM technology, fluorophores that are contained in the specimen or have been introduced into the specimen are, as a rule, excited with laser light which is formed into a so-called “light sheet” or, rather, which is passed across the specimen in such a manner that effectively (in the course of the observation period) the form of a light sheet results. Using one light sheet at a time, a plane at a certain depth of the specimen is illuminated, and by means of this illumination, an image of the specimen in this particular plane is obtained.